Because drug smugglers don’t put out annual reports, it’s difficult to gauge how many panga boats from Mexico unload bales of marijuana on California beaches. But authorities say it is substantial and, apparently, smugglers don’t take the holidays off.

San Luis Obispo County Sheriff’s deputies arrested eight people in a van near San Simeon at 3:30 a.m. on Thanksgiving morning and confiscated and estimated 3 tons of baled marijuana. A search of the beach turned up a 35-foot panga boat powered by three outboard engines.

The open-air fishing boats, up to 45 feet long but ill-equipped for the high seas, carry up to five or six tons of weed. The lightweight craft travel frequently up and down the coast and make intermittent appearances in the media. Sometimes they are waylaid at sea by the U.S. Coast Guard, sometimes they are confronted on land and sometimes only an empty vessel or stray floating bale of marijuana marks their fleeting presence. They usually get away.

Why would pot smugglers want to smuggle pot into a state where growing and smoking medical marijuana is legal and there are no shortage of illegal growers? Because, authorities say, a lot of the pot is headed for the Midwest and East where, presumably, the standards are different. Inquisitr says one is more likely to hear sheriff’s deputies in Santa Cruz—where they know good pot—talking about how low grade the weed is, than perps and street price.

The San Luis Obispo Tribune said its archives indicated the holiday bust was the 15th recorded in its archives since May 2012 for just the 54-mile stretch between Ragged Point and Montaña de Oro.

The panga boat incursions, which authorities say began around six years ago but intensified recently, have drawn the attention of Homeland Security types, who worry about surreptitious visits of a more serious nature. Here are some of this year’s busts from all along the coast:

January 15 A “super panga” hit the beach in Cayucos. The San Luis Obispo Sheriff's Office calls them super pangas because they are 15 to 25 feet longer than the typical 30-foot boat. It was powered by two 350-horse-power outboard engines. The boat was spotted by a bird watcher and by the time officers arrived, the perps were gone. But they left 2 tons of pot behind. “Deputies say the pangas originate from Northern Baja Mexico and can get to the Central Coast in a day or two.”

March 6 Vandenberg Air Force Base was invaded by a 20-foot aluminum panga boat. The boat was abandoned boat on shore with what was described as $1 million worth of marijuana, but no poundage was reported. After a base lockdown and an exhaustive search of the 99,000-acre installation, Colonel Nina Armagno said, “We have determined that there is no threat to the base and the local community.”

April 7 It is safe to assume that midnight drops on secluded beaches are the preferred scenarios for marijuana deliveries. But something went awry and a 30-foot panga boat ended up at a popular surfing beach in Malibu during the day. Los Angeles County Sheriff’s deputies arrested three people, one of whom was trying to blend in with other beachgoers, and confiscated two tons of marijuana near Leo Carrillo State Park

May 12 A panga boat with “Sinaloa” printed on its side was found abandoned just feet from a van on Pescadero State Beach at Half Moon Bay. (The Sinaloa Cartel is infamous.) Both were abandoned, but half a ton of marijuana was left behind. U.S. Department of Homeland Security spokesman Andrew Muñoz told NBC Bay Area, “This year, 100 ‘maritime smuggling’ operations have been documented along the California coast, netting 30 tons of seized contraband totaling $50 million.”

May 26 A 40-foot panga boat, confronted by the Coast Guard, dumped two tons of marijuana in the water 130 miles southwest of the San Diego coast. Three people were arrested.

June 27 A Coast Guard cutter intercepted a panga boat and confiscated 7,600 pounds of pot 160 miles from San Diego. Three people were arrested.

July 29 A C-130 Hercules aircraft spotted a couple of panga boats 180 miles southwest of San Diego and when the three Coast Guard cutters closed in, the occupants made a run for it. Four men left six tons of marijuana in one boat and took off in the other. They did not escape.

August 1 San Mateo County narcotics officers were waiting for a panga boat after a tip from Homeland Security. The boat offloaded 5,148 pounds of marijuana onto two waiting vans, and then the officers offloaded nine suspects from the vans.

August 21 The Mexican Navy joined the Coast Guard in a joint operation in international waters 150 miles from the coast. The panga boat, three suspects and one ton of marijuana were turned over to Mexico.